With the growing social concern about the emission of ever-increasing amounts of industrial gases, the need for effective gas-scrubbing devices has increased correspondingly.
Many types of gas-scrubbing devices are already known but such devices are extremely expensive and have limited useful operating lives particularly when they are operated at the high temperatures required for the destruction, deactivation or extraction of toxic waste materials. For example, gas-scrubbing devices constructed of fire-brick or other refractory material are eventually thermally degraded to such an extent that they must be rebuilt, simple repair eventually becoming impossible. Clearly, such reconstruction is extremely expensive and, during such reconstruction, waste gases are vented untreated presenting additional problems.
Gas scrubbers for the removal of particulate waste material usually take the form of cyclone chambers, in which the gases are whirled around at high speed in a conical chamber. The particulate matter is thus separated from the gaseous waste, and falls to the bottom of the chamber.
Gas scrubbers for waste gases containing vaporized contaminants such as organic solvent vapors, usually take the form of incinerators or after-burners designed to raise the temperature of the gases sufficiently to cause oxidation of the vapor. Both forms of gas scrubbers have severe limitations, such as are well recognized in the industry.
In particular, the operation of cyclone-type scrubbers is not suitable for high temperature gases, since they cause rapid destruction of the metallic cyclone chambers, unless the same are made of special high temperature resistant materials, at greatly increased cost. The incineration of gases containing entrained vapors such as organic solvents, while not being generally within the scope of the invention, also presents similar problems of handling high temperature gases. In particular the gases when they exit the incinerator chamber in which the vapors are oxidized, may be in the region of 2,500.degree. F., which presents significant problems in the design and construction of the ducts and chimneys handling these gases.
It is accordingly an object of this invention to provide a gas-scrubbing device of lower cost metallic construction for the aforesaid purposes and which device has a longer useful operating device than those previously known.
It is a further object of this invention to provide a gas-scrubbing device of metallic construction and in which the thermal degradation of structural parts thereof is significantly reduced.
Yet another object of this invention is to provide a gas-scrubbing device of metallic construction and in which the replacement of structural components thereof when eventually required is facilitated thereby delaying the need for total or at least extensive reconstruction of the device.
A further object of the invention is to provide an gas-scrubbing device of metallic construction and which is constructed in such a manner that the replacement of structural parts can be effected much more quickly and at a much lower cost than with gas-scrubbing devices heretofore known.
Other objects of the invention and the advantages presented thereby will become apparent as the description herein proceeds.